Reinfection with SARS-CoV-2 and Failure of Humoral Immunity: a case report
First Author: Goldman et al.
Journal/preprint name: MedRxiv
Paper DOI: https://doi.org/10.1101/2020.09.22.20192443
Tags: Clinical-Case study, Immunology/Immunity
Goldman et al. define a new SARS-CoV-2 reinfection case by whole viral genome sequencing and correlate the lack of protection to a weak humoral immune response. This preprint describes a case-study from a patient that was found re-infected 140 days (March and July) after the first SARS-CoV-2 PCR positive test but found less severely ill in re-infection. Whole genome sequencing of the viruses indicated that first and second infection were not due to prolonged viral shedding but to 2 genetically distinct virus. Antibody responses were evaluated only after re-infection and poor responses were found against spike and RBD (receptor binding domain) with a rapid decay. Overall, this pre-print describes a rare case of re-infection and correlates it with a failure in humoral immune responses.
Description of a re-infection SARS-CoV-2 case after 140 days of the first infection
Whole genome sequence of the virus shows 2 genetically distinct virus, last with D614G mutation.
Poor anti-spike and anti-RBD antibody responses were found in the patient after re-infection
No evidence of antibodies blocking RBD-ACE2 binding
Impact for COVID-19 research:
It describes a case of re-infection and correlates it with profound defects in humoral immune responses. Helps to understand the immune correlates for humoral immunity that might prevent re-infection.
Study Type: Patient-case study
Key Techniques: whole genome sequencing,
The authors attribute re-infection to a poor humoral response from the first infection but there is no proof to that, other than a general weak humoral immunity for this patient after re-infection.
The authors link the re-infection to the fact that first generated immune responses can’t protect from re-infection of the now more circulating virus harbouring the D614G mutation. However, most studies show that antibodies against the Spike are able to neutralize WT and D614G viruses and therefore re-infection may be ascribed in this case to malfunctioning of the humoral immunity.